Tilt table



Feb. 4, 1969 v R. E. THORESON ET AL TILT TABLE I of 5 Sheet Filed Sept. 13, 1966 Hlllllli LIIUTLUHIIHIF F'IG l MAUS on 5PM,

Feb. 4, 1969 R. E. THORESON ET'AL 3,425,365

TILT TABLE Filed Sept. 13, 1966 Sheet 2 0f ulu INVENTORS 05427: Tao/Pisa 5 45 7190? M1406 A TTORNEYS Feb. 4, 1969 THORESGN 'ET AL 3,425,365

TILT TABLE Filed Sept. 13, 1966 L a i I Q 1 70 K i 26 i I 64 /2 I EX "74/ I g 8 68 /36 I I I 0) II "1 F'IG.4

A 7' TORNE VS United States Patent 2 Claims This invention relates to tilt tables, and more particularly to a table which tilts automatically from a horizontal to an inclined position in response to the shifting of the center of gravity of a load disposed thereon.

The table disclosed herein is specifically adapted to be used to facilitate the withdrawal of granular material from containers. For example, in the plastics field, the particulate plastic material is shipped to the user in large containers from which it is withdrawn by means of a vacuum hose or the like for delivery to a drying machine and then ultimately to the plastic forming machine. As the level of material in the container recedes, it becomes more difficult to withdraw the material, and the container must be manipulated in order to ensure that it is completely emptied. Manual handling of these containers is undesirable, as they are large and cumbersome.

It is therefore the principal object of the invention to provide a table upon which such containers of material may be placed for emptying, which table is provided with a load supporting top or table member normally disposed in a horizontal position, but tiltable to an inclined position as the container is progressively emptied, so that the container may be completely exhausted of material automatically.

Another object is the provision of such a table wherein the container supporting table member is pivotally mounted on a stationary base for movement between horizontal and tilted positions, with means interposed between the table member and base permitting movement of the table member to the inclined position during emptying of the container for ensuring complete removal of the material from the container.

A concomitant object is to provide such a table including releasable latch means for latching the table member in its horizontal position.

Other objects, advantages and meritorious features will more fully appear from the following specification, claims, and accompanying drawings, wherein:

FIG. 1 is a side elevation of a tilt table embodying the invention taken along line 11 of FIG. 2;

FIG. 2 is a top elevation of the tilt table of FIG. 1;

FIG. 3 is an enlarged view of the latch means for latching the table in one position, taken along line 3-3 of FIG. 2;

FIG. 4 is a side elevation similar to FIG. 1, showing motion retarding means preventing abrupt movement of the table between its horizontal and tilted positions; and

FIG. 5 is a partial top elevation of the tilt table of FIG. 4.

Referring now more particularly to FIGS. 1-3 of the drawings, the tilt table is shown as comprising a base having a pair of upright supports 12 and 14 fixedly secured thereto in spaced apart relation. Extending between the supports is a generally horizontal shaft 16 which is secured within apertures in the supports against axial movement by a suitable retaining means (not shown). The supports 12 and 14 are preferably of channel construction, as shown in FIG. 2, for strength and rigidity, and each is reinforced by a web 18 or the like fastened to the base 10.

A generally planar table member 20 is provided having a pair of depending blocks 22 and 24 fixed to the underside thereof as by welding. Each block is apertured as at ice 26 (see FIG. 1) to define a bearing surface embracing the shaft 16. This construction permits the table member to rotate on the shaft 16 from a horizontal position shown in solid outline at 20 in FIG. 1 to a tilted position shown at 20' therein. By reference to FIG. 2 it can be seen that the shaft 16 is positioned spaced from and with its axis parallel to a diagonal of table member 20. When a container full of material is centrally positioned on table member 20, the center of gravity will lie spaced from the axis of shaft-16 toward the corner of the table at the lower right in FIG. 2, which will act to keep the table member in a horizontal position. v

Upstanding from the table member 20 at one corner thereof is an upright support 28, which is connected at its upper end to two inclined supports, one of which is shown at 30 in FIG. 1, to prevent a container such'as a box or the like from sliding off the table when in its tilted position.

Upstanding from the base 10 and fixed thereto at the corner diagonally opposite member 28 is an angle member 36 which abuts the underside of thetable member 20 when the latter is swung to its horizontal position. Latch means (in the embodiment shown there are two), generally indicated at 38, are mounted on the table 20, and a pin 40 projects from each face of the member 36 for engagement by a latch to lock the table in its horizontal position. Each latch means 38 comprises a latch arm 42 defining a hook portion 44 adjacent its lower end, which arm is pivotally mounted on a bolt orthe like 46 projecting through a depending flange 48 on member 20. A coil spring 50 encircles the bolt 46 and is fixed at opposite ends to flange 48 and arm 42 respectively. A washer 52 and nut means 54 on bolt 46 retain the spring 50 in position. The spring 50- acts as both a torsion and a compression spring, urging the arm 42 to rotate on bolt 46 toward its locked position engaging pin 40, and also biasing the arm inwardly toward the member 46 to insure engagement with pin 40.

As can be seen in FIG. 3, when the latch means 38 are in latched position, the table flange 48 and member 36 are spaced apart slightly. The hook portion '44 of.

each latch arm 42 has an inclined upper edge 56, preventing accidental disoldgment of the arm from pin 40. When it is desired to unlatch arm 42, table member 20 is pressed downwardly against the top of member 36, and the latch arm 42 may then be easily pivoted out of engagement with pin 40, as the edge 56 will be disengaged from the 7 pin. As the-center of gravity of a fully loaded box lies closer to the latched corner than the axis of shaft 16- about which the table member pivots, when a loaded box is placed on the table, the weight will tip the table slightly downwardly against member 36, enabling the latches 38 to be unlatched. Further, each latch arm 42 is equipped with a block portion 58 on the inner surface thereof, so that when the arm is released from pin 40, it may be swung to a position where the block 58 becomes hooked over the edge of member 36, it being retained in this position under the influence of spring 50. Thus the latch arm 42 may be retained in its unlocked position when the table 20 and member 36 are in the relative positions shown in FIG. 3. As table 20 tilts away from member 36, the block 58 no longer engages member 36, and the .arm 42 is returned to the position shown by spring 50 so that when the table is again swung to its horizontal position, the latch arm will automatically lock on pin 40.

In operation, the table member 20 of FIGS. 1-3 is latched in its horizontal position by the latch means 38 (see FIG. 1) and a container or box 60 filled with material which is to be fed to a processing machine or the like is placed on the table 20. The latches 38 are then released, and the weight of the full container is suflicient to keep the table member in its horizontal position be-.

cause of the offset of shaft 16. The material in the container 60 is Withdrawn as by a vacuum hose or the like, preferably with the hose and positioned toward the right of the container as shown in FIG. 1. As material is withdrawn from this one side of the container the center of gravity of the load shifts toward the left as seen in FIG. 1, and when the center of gravity shifts to the left far enough, i.e., past shaft 16, the table begins to tilt, until it finally reaches the position indicated at 20 in FIG. 1. In this position, the remaining material in the container 60 is concentrated in the lowermost corner thereof in the area indicated by numeral 62, and thus the material may be completely exhausted from the container by merely shifting the position of the vacuum hose or the like and without the necessity of manipulating the container or the material therein. When the container is completely empty, it is removed from the tilt table, the table is returned to its horizontal position and latched thereat, and a fresh container filled with material is placed on the table member 20. While it is contemplated that the particular material be withdrawn by a vacuum hose or the like, other suitable means may be employed.

Referring now to FIGS. 4 and 5, there is shown a preferred construction for the tilt table including means for retarding the movement of the table member from its horizontal to its tilted position. The same reference numerals have been used to refer to parts that are identical to those previously described. Such device is provided to prevent abrupt table movement and provide a smooth, relatively slow swinging of the table to its tilted position.

As shown, the motion retarding means comprises a system of extensible dampers, each of which are of the general type used by the automotive industry, commonly known as shock absorbers, and readily available from any one of a number of manufacturers. Thus the internal construction of these devices is well known, and need not be described in detail. In the embodiment shown, three such devices are provided, two of which, shown at 64 and 66, are in parallel, and the third, shown at 68, in series with the first two. Members 64 and 66 are pivotally connected at their upper ends to the underside of table member 20 by bolt and nut means or the like projecting through blocks 70 fixed to the table member, while one end of member 68 is similarly pivotally connected to a support 72 affixed to the base 10. A pair of spacedapart links 74 and 76 are pivotally mounted at one end on a block 78 secured to the base 10, and the opposite ends of the links are interconnected by a tie rod or the like 80, to which the remaining ends of each of the members 64, 66 and 68 are pivotally connected.

In the normal at rest position, that is with table member 20 disposed horizontally, the motion retarding mechanism is in the position shown in solid outline in FIG. 4. In this position the links 74 and 76 rest against a stop 82. A vacuum hose, preferably secured to a swingable boom (not shown) is introduced into the full container 60 toward the right-hand side thereof, and material is withdrawn, the latches 38 having been previously released. As material is sucked out of the right-hand portion of container 60, the center of gravity shifts to the left, and

the table will start to tilt in a counterclockwise direction about shaft 16 when the center of gravity shifts to the left of the shaft. As the table 20 begins to shift, its movement is retarded or slowed by the members 64, 66 and 68, which act as dampers, extending relatively slowly until they reach their fully extended position, such as shown in phantom at 64 FIG. 4. In this position link 74 has pivoted to the position shown in phantom at 74, and table member 20 is in its fully tilted position shown at 20'. As the container is gradually exhausted the vacuum hose (not shown) is swung on its boom until it projects into the lowermost corner of the container to completely empty material therefrom.

What is claimed is:

1. A table having a tiltable top comprising a base adapted to rest upon a floor, a pair of rigid support members connected to the base and upstanding therefrom in spaced apart relation, a shaft extending between and supported by said support members adjacent opposite ends of the shaft, a square table top member having a fiat upper surface and at least two bearing blocks depending from the top member and journaled on said shaft for permitting pivotal movement of the top member with respect to said base, an upright stop member fixed to said base and projecting into abutment with said table top member at one corner thereof when the latter is in its horizontal position, the longitudinal axis of said shaft extending under said table top member parallel to and spaced laterally from a diagonal of the top member in a direction opposite said one corner, and dampening means for retarding table movement including first extensible damper means connected at one end to said base and second extensible damper means connected at one end to said table member, with the opposite ends of said first and second damper means being coupled together, whereby initial table movement is retarded primarily by said first damper means and further table movement is retarded primarily by said second damper means.

2. The invention as defined in claim 1 characterized in that at least one latch member is pivotally mounted on said table member and a pin projects laterally from said upright stop member, with the latch having a hooked end portion for engaging said pin in one position of rotation to lock said table member against movement from its horizontal position.

References Cited UNITED STATES PATENTS 520,720 5/1894 Armstrong 2l4l30 1,404,335 1/1922 Barnes 2l477 1,534,797 4/1925 McLeod 214 2,011,627 8/1935 Graham 2543 2,963,248 12/1960 Anderson 108-2 2,787,509 4/ 1957 Hardrath 1082 ROBBY R. GAY, Primary Examiner.

G. O. FINCH, Assistant Examiner.

US. Cl. X.R. 108-001 

